HIAT2015 - List of Authors (Kase, M.)

Paper

Title

Page

History of Solid Disk Improvement for Rotating Charge Stripper

1

H. Hasebe, N. Fukunishi, H. Imao, O. Kamigaito, M. Kase, H. Kuboki, H. Okuno
RIKEN Nishina Center, Wako, Japan

In 2007, we installed a rotating disk stripper device at the final charge stripping section for the uranium (U) beam acceleration at RIKEN RI Beam Factory. The first rotating carbon disk (C-disk) stripper was useless because of its poor surface flatness and unexpected low density. In 2012, we started the stable U beam operation using beryllium (Be) as the disk material. We successfully improved the flatness of the Be-disk by special polishing technique in 2014, and the transmission efficiency was greatly improved as well. However, it seemed to be impossible that the Be-disk withstood the heat load of the expected intensity in future, considering its deformation. Then, the polishing technique for the Be-disk improvement was applied to the Glassy carbon (GC) disk. The GC-disk flatness was improved maintaining high density. In addition, a tested high-density highly oriented graphite sheet, which is fabricated from a high polymer film in high temperature and high pressure conditions, can be applied as the charge stripping disk since the better stripping efficiency and transmission value than those of Be and the C-disk were realized.

Slides MOA1C01 [3.376 MB]

MOPA09

RIKEN Ring Cyclotron (RRC)

1

Y. Watanabe, M. Fujimaki, N. Fukunishi, E. Ikezawa, O. Kamigaito, M. Kase, K. Kumagai, T. Maie, J. Ohnishi, H. Okuno, K. Ozeki, N. Sakamoto, K. Suda, S. Watanabe, K. Yamada
RIKEN Nishina Center, Wako, Japan
S. Fukuzawa, M. Hamanaka, S. Ishikawa, K. Kobayashi, R. Koyama, T. Nakamura, M. Nishida, M. Nishimura, J. Shibata, N. Tsukiori, K. Yadomi
SHI Accelerator Service Ltd., Tokyo, Japan

The RIKEN Ring Cyclotron (RRC) has been in stable operation over 28 years, and has been used for supplying many types of heavy-ion beams for various experiments. Since 2007, it has also been used for supplying beams to the three Ring Cyclotrons at the Radioactive Isotope Beam Factory (RIBF). The RRC has three types of injectors: the AVF cyclotron for comparatively light ions, variable-frequency linac for heavy-ions (RILAC), and the RIKEN Heavy-ions Linac 2 (RILAC2) for using high-intensity very-heavy ions. The total operation time of the RRC is more than 4000 h/year. Recently, some problems caused by age-related deterioration have often been occurring in the RRC. Some main coils of sector magnets had a sign of layer short. Two Magnetic Deflection Channels and some electrodes of Electrostatic Deflection Channel were damaged by some beam-loss. Several leaks of vacuum have happened at a feed-through of trim coils in the E-sector, at a bellows between the Resonator No.2 and the S-sector magnet, and at some copper cooling water pipes in the Resonator No.1 and the Resonator No.2. These present statuses of the RRC are presented in this paper.

MOPA10

Development of Low-Energy Heavy-Ion Beams by the RIKEN AVF Cyclotron and Hyper ECR Ion Source of CNS

1

Y. Kotaka, N. Imai, H. Muto, Y. Ohshiro, S. Shimoura, S.-I. Watanabe, H. Yamaguchi
CNS, Saitama, Japan
A. Goto
Yamagata University, Yamagata, Japan
K. Hatanaka
RCNP, Osaka, Japan
M. Kase, S. Kubono
RIKEN Nishina Center, Wako, Japan

The application of low-energy heavy-ion beams enhances production of radioisotope (RI) and studies of nuclear astrophysics.　The Center for Nuclear Study (CNS) of the University of Tokyo and RIKEN Nishina Center have been developing the RIKEN AVF Cyclotron (AVF) and the Hyper ECR Ion Source (IS) of CNS to expand available ions and their acceleration energies as well as to increase the beam intensity for studies at the low-energy RI beam separator CRIB * and others. Renovation of central region of the AVF expands the acceptance of injection beam, so that 4He beam is now available at a higher energy of 12.5MeV/u under the constraint that the maximal Dee voltage is 50kV. Intensities of metallic ions extracted from the IS have been increased by developing three kinds of vaporization methods, multi-hole micro-oven, non-axial rod and MIVOC. Plasma spectroscopy ** is applied to monitor the intensities of highly charged ions in the IS. For systematic study of transport efficiencies, several beam diagnostic devices have been added. One key device is a set of a multi-hole slit and a viewer of the beam image (pepper-pot emittance monitor ***), which gives four-dimensional phase space.
* Y. Yanagisawa et al., Nucl. Instr. and Meth. Phys. Res. A539 (2005) 74
** H. Muto et al., Rev. Sci. Instr. 85 (2014) 02A905
*** T. Hoffmann et al., Proc. 9th BIW2000, Cambridge, USA, PP.432-439

MOPA12

Status Report of the Operation of the RIKEN AVF Cyclotron

K. Suda, M. Fujimaki, N. Fukunishi, T. Kageyama, O. Kamigaito, M. Kase, M. Komiyama, K. Kumagai, T. Maie, M. Nagase, T. Nagatomo, T. Nakagawa, H. Okuno, N. Sakamoto, A. Uchiyama, T. Watanabe, Y. Watanabe, K. Yamada
RIKEN Nishina Center, Wako, Japan
S. Fukuzawa, M. Hamanaka, S. Ishikawa, K. Kobayashi, R. Koyama, T. Nakamura, M. Nishida, M. Nishimura, J. Shibata, N. Tsukiori, K. Yadomi
SHI Accelerator Service Ltd., Tokyo, Japan
Y. Kotaka, Y. Ohshiro, S. Yamaka
CNS, Saitama, Japan

The RIKEN AVF cyclotron was commissioned in 1989. Since then, it has been operated as an injector for the RIKEN ring cyclotron. The AVF cyclotron also provides low energy ion beams for the Radio-Isotope Beam separator (CRIB) of the Center for Nuclear Study (CNS), the University of Tokyo, as well as to produce RIs for commercial use. The operating time is more than 3,000 hours per year. We will report the operating status (nuclear species, energy, supply destination of accelerated ions), troubles, maintenance work, and the improvement of ion sources and diagnostics tools for the period from August 2014 to July 2015.

MOPA32

Operation of Gas Strippers at RIBF; Thinning Effect of Gas Strippers for High-Intensity Very Heavy Ion Beams

H. Imao
RIKEN Nishina Center for Accelerator-Based Science, Wako, Saitama, Japan
H. Hasebe, O. Kamigaito, M. Kase, H. Okuno
RIKEN Nishina Center, Wako, Japan
H. Kuboki
KEK, Tokai, Ibaraki, Japan

Intensity upgrade of very-heavy ions such as U and Xe beams is one of the main concerns at the RIKEN Radioactive Isotope Beam Factory (RIBF). In the acceleration of them, the possible output intensities have been principally limited by the lifetime problem of the carbon foil strippers. In previous years, realization of the gas strippers was an important breakthrough for intensity upgrade of very heavy ion beams. The recirculating He gas stripper for uranium beams has been stably operated since 2012. The air stripper for xenon beams was also successfully operated in 2013. For pursuing further high intensities of very heavy ion beams, we need to understand the application limit of the present gas strippers. Density reduction of gas along the trajectories of the beams caused by the heat load (thinning effect) is a factor which will determine the application limit of the gas stripper. We will present the recent operational situation of gas strippers involving the study of the gas thinning effect.

WEPB01

Status Report on the Operation of the RIBF Ring Cyclotrons

1

K. Ozeki, T. Dantsuka, M. Fujimaki, T. Fujinawa, N. Fukunishi, H. Hasebe, Y. Higurashi, E. Ikezawa, H. Imao, T. Kageyama, O. Kamigaito, M. Kase, M. Kidera, M. Komiyama, K. Kumagai, T. Maie, M. Nagase, T. Nagatomo, T. Nakagawa, M. Nakamura, J. Ohnishi, H. Okuno, N. Sakamoto, K. Suda, A. Uchiyama, S. Watanabe, T. Watanabe, Y. Watanabe, K. Yamada, H. Yamasawa
RIKEN Nishina Center, Wako, Japan
S. Fukuzawa, M. Hamanaka, S. Ishikawa, K. Kobayashi, R. Koyama, T. Nakamura, M. Nishida, M. Nishimura, J. Shibata, N. Tsukiori, K. Yadomi
SHI Accelerator Service Ltd., Tokyo, Japan
Y. Kotaka
CNS, Saitama, Japan

Operational status of four ring cyclotrons (RRC, fRC, IRC, SRC) from August 2014 to July 2015 is reported. We are engaging in the improvements and adjustments for increasing beam intensities year after year, and maintenances for the stabilization of beam supply. In these contributions, we will report the past performances of accelerated beams, statistics of operational and tuning time on corresponding period, as well as failures and copings with them.

WEPB14

Heavy-Ion Beam Acceleration at RIKEN for the Super-Heavy Element Search

E. Ikezawa, M. Fujimaki, Y. Higurashi, O. Kamigaito, M. Kase, M. Komiyama, T. Nakagawa, K. Ozeki, N. Sakamoto, K. Suda, A. Uchiyama
RIKEN Nishina Center, Wako, Japan
T.O. Ohki, K. Oyamada, M. Tamura
SHI Accelerator Service Ltd., Tokyo, Japan

The RIKEN heavy ion linac (RILAC) is composed of a variable-frequency Wideröe linac, an 18 GHz ECR ion source, a variable-frequency folded-coaxial radio frequency quadrupole linac (FC-RFQ) as a pre-injector, and a Charge-State Multiplier system (CSM) as a booster. The operation of RILAC was started to supply heavy ion beams for experiments in 1981. The 18 GHz ECR ion source and the FC-RFQ were installed in 1996. The CSM was installed in 2000. The maximum beam energy, boosted by the CSM, is 6.0 MeV/nucleon. A GAs-filled Recoil Isotope Separator (GARIS) was moved from the E1 experiment room of the RRC to the No. 1 target room of the RILAC in 2000. In RIKEN Nishina center, the experiment on the super-heavy element (Z=113) search was carried out at RILAC from September 2003 to October 2012. As a result, three events for Z=113 have been successfully observed. The heavy-ion beam acceleration at RIKEN for the super-heavy element search will be reported.

WEPB24

Development of an Online Emittance Monitor for Low Energy Heavy Ion Beams

1

V. Tzoganis, O. Kamigaito, M. Kase, T. Nagatomo, T. Nakagawa
RIKEN Nishina Center, Wako, Japan
V. Tzoganis
The University of Liverpool, Liverpool, United Kingdom
V. Tzoganis
Cockcroft Institute, Warrington, Cheshire, United Kingdom

RIKEN's 18 GHz ECR ion source supplies the AVF cyclotron with beams ranging from protons to heavy ions as xenon. From comparison with the use of the RILAC (RIKEN Linear Accelerator) and beam transport simulations it was found that the transport efficiency is much lower. To this extend and with the aim to understand the ECR beam production, beam dynamics and optimize the beam transfer we have developed an emittance monitor based on the pepperpot method. The device is composed of a perforated copper plate, transparent scintillator and a CMOS camera for image capturing. Parameters of interest for scintillator's performance are the light yield and radiation hardness. Quartz was found to be resilient to damage and having linear light emission. A real time algorithm written in LabVIEW manages the data acquisition and the 4D phase space distribution calculation. Provided this information, we can investigate parameters such as inter-plane correlation and emittance dependence on extraction specifications, beam current and the magnetic field in the ion source. In this contribution we are presenting the emittance meter design, algorithm description and a set of typical measurements.

WEPB26

Emittance Measurement of Low Energy Proton Beam Extracted from RIKEN 18-GHz Superconducting ECR Ion Source with the Pepper-Pot Emittance Meter

T. Nagatomo
RIKEN, Saitama, Japan
O. Kamigaito, M. Kase, T. Nakagawa, V. Tzoganis
RIKEN Nishina Center, Wako, Japan
V. Tzoganis
The University of Liverpool, Liverpool, United Kingdom
V. Tzoganis
Cockcroft Institute, Warrington, Cheshire, United Kingdom

Emittance measurements are of high importance for beam quality assessment and optimization of beam transport. For the case of ECR ion sources providing highly charged heavy ions, the naturally high emittance of beams extracted under strong magnetic field poses extra challenges for efficient beam transport. Moreover, the transverse inter-plane correlation of the 4D emittance is considered to be important so that the beam brightness increases. For the further understanding of the ECR source and increasing the brightness we have developed emittance monitor based on the pepperpot method that allows the measurement of the 4D emittance. The emittance meter consists of a pepperpot plate and a transparent scintillating screen behind it. As a first step, the emittance meter is installed behind the analyzing magnet, and we have obtained beamlet images with 6.52-keV proton (~100eμA) provided by the RIKEN 18-GHz Superconducting ECR ion source. The beam transport is simulated with the Monte Carlo method (GEANT4). The estimated spatial and phase space distribution are reasonably consistent with those obtained with the emittance meter. Ways to optimize the beam transport are also discussed.

WEPB29

Observation of Sublimation Effect of Mg and Ti Ions at the Hyper-Electron Cyclotron Resonance Ion Source

H. Muto, Y. Kotaka, S. Kubono, Y. Ohshiro, S. Shimoura, S.-I. Watanabe, H. Yamaguchi, S. Yamaka
CNS, Saitama, Japan
T. Hattori
NIRS, Chiba-shi, Japan
M. Kase, S. Kubono
RIKEN Nishina Center, Wako, Japan
K. Kobayashi, M. Nishimura
SHI Accelerator Service Ltd., Tokyo, Japan
M. Oyaizu
KEK, Ibaraki, Japan

Light intensities of a grating monochromator during plasma chamber baking and 24Mg⁸⁺ and 48Ti¹³⁺ beam operation were observed at the Hyper-Electron Cyclotron Resonance ion source. During chamber baking almost all light intensities were Fe I and Fe II. However, when MgO or TiO2 rod was inserted into the plasma and the beam operation was started the light intensity spectrum was drastically changed and most of the Fe I and Fe II lights were disappeared and Mg or Ti light intensities were coming out. In this paper we describe vacuum conditions of ECR ion source during chamber baking and beam tuning.

Poster WEPB29 [3.227 MB]

Paper	Title	Page
MOA1C01	History of Solid Disk Improvement for Rotating Charge Stripper	1
	H. Hasebe, N. Fukunishi, H. Imao, O. Kamigaito, M. Kase, H. Kuboki, H. Okuno RIKEN Nishina Center, Wako, Japan
	In 2007, we installed a rotating disk stripper device at the final charge stripping section for the uranium (U) beam acceleration at RIKEN RI Beam Factory. The first rotating carbon disk (C-disk) stripper was useless because of its poor surface flatness and unexpected low density. In 2012, we started the stable U beam operation using beryllium (Be) as the disk material. We successfully improved the flatness of the Be-disk by special polishing technique in 2014, and the transmission efficiency was greatly improved as well. However, it seemed to be impossible that the Be-disk withstood the heat load of the expected intensity in future, considering its deformation. Then, the polishing technique for the Be-disk improvement was applied to the Glassy carbon (GC) disk. The GC-disk flatness was improved maintaining high density. In addition, a tested high-density highly oriented graphite sheet, which is fabricated from a high polymer film in high temperature and high pressure conditions, can be applied as the charge stripping disk since the better stripping efficiency and transmission value than those of Be and the C-disk were realized.
	Slides MOA1C01 [3.376 MB]

MOPA09	RIKEN Ring Cyclotron (RRC)	1
	Y. Watanabe, M. Fujimaki, N. Fukunishi, E. Ikezawa, O. Kamigaito, M. Kase, K. Kumagai, T. Maie, J. Ohnishi, H. Okuno, K. Ozeki, N. Sakamoto, K. Suda, S. Watanabe, K. Yamada RIKEN Nishina Center, Wako, Japan S. Fukuzawa, M. Hamanaka, S. Ishikawa, K. Kobayashi, R. Koyama, T. Nakamura, M. Nishida, M. Nishimura, J. Shibata, N. Tsukiori, K. Yadomi SHI Accelerator Service Ltd., Tokyo, Japan
	The RIKEN Ring Cyclotron (RRC) has been in stable operation over 28 years, and has been used for supplying many types of heavy-ion beams for various experiments. Since 2007, it has also been used for supplying beams to the three Ring Cyclotrons at the Radioactive Isotope Beam Factory (RIBF). The RRC has three types of injectors: the AVF cyclotron for comparatively light ions, variable-frequency linac for heavy-ions (RILAC), and the RIKEN Heavy-ions Linac 2 (RILAC2) for using high-intensity very-heavy ions. The total operation time of the RRC is more than 4000 h/year. Recently, some problems caused by age-related deterioration have often been occurring in the RRC. Some main coils of sector magnets had a sign of layer short. Two Magnetic Deflection Channels and some electrodes of Electrostatic Deflection Channel were damaged by some beam-loss. Several leaks of vacuum have happened at a feed-through of trim coils in the E-sector, at a bellows between the Resonator No.2 and the S-sector magnet, and at some copper cooling water pipes in the Resonator No.1 and the Resonator No.2. These present statuses of the RRC are presented in this paper.

MOPA10	Development of Low-Energy Heavy-Ion Beams by the RIKEN AVF Cyclotron and Hyper ECR Ion Source of CNS	1
	Y. Kotaka, N. Imai, H. Muto, Y. Ohshiro, S. Shimoura, S.-I. Watanabe, H. Yamaguchi CNS, Saitama, Japan A. Goto Yamagata University, Yamagata, Japan K. Hatanaka RCNP, Osaka, Japan M. Kase, S. Kubono RIKEN Nishina Center, Wako, Japan
	The application of low-energy heavy-ion beams enhances production of radioisotope (RI) and studies of nuclear astrophysics.　The Center for Nuclear Study (CNS) of the University of Tokyo and RIKEN Nishina Center have been developing the RIKEN AVF Cyclotron (AVF) and the Hyper ECR Ion Source (IS) of CNS to expand available ions and their acceleration energies as well as to increase the beam intensity for studies at the low-energy RI beam separator CRIB * and others. Renovation of central region of the AVF expands the acceptance of injection beam, so that 4He beam is now available at a higher energy of 12.5MeV/u under the constraint that the maximal Dee voltage is 50kV. Intensities of metallic ions extracted from the IS have been increased by developing three kinds of vaporization methods, multi-hole micro-oven, non-axial rod and MIVOC. Plasma spectroscopy is applied to monitor the intensities of highly charged ions in the IS. For systematic study of transport efficiencies, several beam diagnostic devices have been added. One key device is a set of a multi-hole slit and a viewer of the beam image (pepper-pot emittance monitor ), which gives four-dimensional phase space. Y. Yanagisawa et al., Nucl. Instr. and Meth. Phys. Res. A539 (2005) 74 H. Muto et al., Rev. Sci. Instr. 85 (2014) 02A905 * T. Hoffmann et al., Proc. 9th BIW2000, Cambridge, USA, PP.432-439

MOPA12	Status Report of the Operation of the RIKEN AVF Cyclotron
	K. Suda, M. Fujimaki, N. Fukunishi, T. Kageyama, O. Kamigaito, M. Kase, M. Komiyama, K. Kumagai, T. Maie, M. Nagase, T. Nagatomo, T. Nakagawa, H. Okuno, N. Sakamoto, A. Uchiyama, T. Watanabe, Y. Watanabe, K. Yamada RIKEN Nishina Center, Wako, Japan S. Fukuzawa, M. Hamanaka, S. Ishikawa, K. Kobayashi, R. Koyama, T. Nakamura, M. Nishida, M. Nishimura, J. Shibata, N. Tsukiori, K. Yadomi SHI Accelerator Service Ltd., Tokyo, Japan Y. Kotaka, Y. Ohshiro, S. Yamaka CNS, Saitama, Japan
	The RIKEN AVF cyclotron was commissioned in 1989. Since then, it has been operated as an injector for the RIKEN ring cyclotron. The AVF cyclotron also provides low energy ion beams for the Radio-Isotope Beam separator (CRIB) of the Center for Nuclear Study (CNS), the University of Tokyo, as well as to produce RIs for commercial use. The operating time is more than 3,000 hours per year. We will report the operating status (nuclear species, energy, supply destination of accelerated ions), troubles, maintenance work, and the improvement of ion sources and diagnostics tools for the period from August 2014 to July 2015.

MOPA32	Operation of Gas Strippers at RIBF; Thinning Effect of Gas Strippers for High-Intensity Very Heavy Ion Beams
	H. Imao RIKEN Nishina Center for Accelerator-Based Science, Wako, Saitama, Japan H. Hasebe, O. Kamigaito, M. Kase, H. Okuno RIKEN Nishina Center, Wako, Japan H. Kuboki KEK, Tokai, Ibaraki, Japan
	Intensity upgrade of very-heavy ions such as U and Xe beams is one of the main concerns at the RIKEN Radioactive Isotope Beam Factory (RIBF). In the acceleration of them, the possible output intensities have been principally limited by the lifetime problem of the carbon foil strippers. In previous years, realization of the gas strippers was an important breakthrough for intensity upgrade of very heavy ion beams. The recirculating He gas stripper for uranium beams has been stably operated since 2012. The air stripper for xenon beams was also successfully operated in 2013. For pursuing further high intensities of very heavy ion beams, we need to understand the application limit of the present gas strippers. Density reduction of gas along the trajectories of the beams caused by the heat load (thinning effect) is a factor which will determine the application limit of the gas stripper. We will present the recent operational situation of gas strippers involving the study of the gas thinning effect.

WEPB01	Status Report on the Operation of the RIBF Ring Cyclotrons	1
	K. Ozeki, T. Dantsuka, M. Fujimaki, T. Fujinawa, N. Fukunishi, H. Hasebe, Y. Higurashi, E. Ikezawa, H. Imao, T. Kageyama, O. Kamigaito, M. Kase, M. Kidera, M. Komiyama, K. Kumagai, T. Maie, M. Nagase, T. Nagatomo, T. Nakagawa, M. Nakamura, J. Ohnishi, H. Okuno, N. Sakamoto, K. Suda, A. Uchiyama, S. Watanabe, T. Watanabe, Y. Watanabe, K. Yamada, H. Yamasawa RIKEN Nishina Center, Wako, Japan S. Fukuzawa, M. Hamanaka, S. Ishikawa, K. Kobayashi, R. Koyama, T. Nakamura, M. Nishida, M. Nishimura, J. Shibata, N. Tsukiori, K. Yadomi SHI Accelerator Service Ltd., Tokyo, Japan Y. Kotaka CNS, Saitama, Japan
	Operational status of four ring cyclotrons (RRC, fRC, IRC, SRC) from August 2014 to July 2015 is reported. We are engaging in the improvements and adjustments for increasing beam intensities year after year, and maintenances for the stabilization of beam supply. In these contributions, we will report the past performances of accelerated beams, statistics of operational and tuning time on corresponding period, as well as failures and copings with them.

WEPB14	Heavy-Ion Beam Acceleration at RIKEN for the Super-Heavy Element Search
	E. Ikezawa, M. Fujimaki, Y. Higurashi, O. Kamigaito, M. Kase, M. Komiyama, T. Nakagawa, K. Ozeki, N. Sakamoto, K. Suda, A. Uchiyama RIKEN Nishina Center, Wako, Japan T.O. Ohki, K. Oyamada, M. Tamura SHI Accelerator Service Ltd., Tokyo, Japan
	The RIKEN heavy ion linac (RILAC) is composed of a variable-frequency Wideröe linac, an 18 GHz ECR ion source, a variable-frequency folded-coaxial radio frequency quadrupole linac (FC-RFQ) as a pre-injector, and a Charge-State Multiplier system (CSM) as a booster. The operation of RILAC was started to supply heavy ion beams for experiments in 1981. The 18 GHz ECR ion source and the FC-RFQ were installed in 1996. The CSM was installed in 2000. The maximum beam energy, boosted by the CSM, is 6.0 MeV/nucleon. A GAs-filled Recoil Isotope Separator (GARIS) was moved from the E1 experiment room of the RRC to the No. 1 target room of the RILAC in 2000. In RIKEN Nishina center, the experiment on the super-heavy element (Z=113) search was carried out at RILAC from September 2003 to October 2012. As a result, three events for Z=113 have been successfully observed. The heavy-ion beam acceleration at RIKEN for the super-heavy element search will be reported.

WEPB24	Development of an Online Emittance Monitor for Low Energy Heavy Ion Beams	1
	V. Tzoganis, O. Kamigaito, M. Kase, T. Nagatomo, T. Nakagawa RIKEN Nishina Center, Wako, Japan V. Tzoganis The University of Liverpool, Liverpool, United Kingdom V. Tzoganis Cockcroft Institute, Warrington, Cheshire, United Kingdom
	RIKEN's 18 GHz ECR ion source supplies the AVF cyclotron with beams ranging from protons to heavy ions as xenon. From comparison with the use of the RILAC (RIKEN Linear Accelerator) and beam transport simulations it was found that the transport efficiency is much lower. To this extend and with the aim to understand the ECR beam production, beam dynamics and optimize the beam transfer we have developed an emittance monitor based on the pepperpot method. The device is composed of a perforated copper plate, transparent scintillator and a CMOS camera for image capturing. Parameters of interest for scintillator's performance are the light yield and radiation hardness. Quartz was found to be resilient to damage and having linear light emission. A real time algorithm written in LabVIEW manages the data acquisition and the 4D phase space distribution calculation. Provided this information, we can investigate parameters such as inter-plane correlation and emittance dependence on extraction specifications, beam current and the magnetic field in the ion source. In this contribution we are presenting the emittance meter design, algorithm description and a set of typical measurements.

WEPB26	Emittance Measurement of Low Energy Proton Beam Extracted from RIKEN 18-GHz Superconducting ECR Ion Source with the Pepper-Pot Emittance Meter
	T. Nagatomo RIKEN, Saitama, Japan O. Kamigaito, M. Kase, T. Nakagawa, V. Tzoganis RIKEN Nishina Center, Wako, Japan V. Tzoganis The University of Liverpool, Liverpool, United Kingdom V. Tzoganis Cockcroft Institute, Warrington, Cheshire, United Kingdom
	Emittance measurements are of high importance for beam quality assessment and optimization of beam transport. For the case of ECR ion sources providing highly charged heavy ions, the naturally high emittance of beams extracted under strong magnetic field poses extra challenges for efficient beam transport. Moreover, the transverse inter-plane correlation of the 4D emittance is considered to be important so that the beam brightness increases. For the further understanding of the ECR source and increasing the brightness we have developed emittance monitor based on the pepperpot method that allows the measurement of the 4D emittance. The emittance meter consists of a pepperpot plate and a transparent scintillating screen behind it. As a first step, the emittance meter is installed behind the analyzing magnet, and we have obtained beamlet images with 6.52-keV proton (~100eμA) provided by the RIKEN 18-GHz Superconducting ECR ion source. The beam transport is simulated with the Monte Carlo method (GEANT4). The estimated spatial and phase space distribution are reasonably consistent with those obtained with the emittance meter. Ways to optimize the beam transport are also discussed.

WEPB29	Observation of Sublimation Effect of Mg and Ti Ions at the Hyper-Electron Cyclotron Resonance Ion Source
	H. Muto, Y. Kotaka, S. Kubono, Y. Ohshiro, S. Shimoura, S.-I. Watanabe, H. Yamaguchi, S. Yamaka CNS, Saitama, Japan T. Hattori NIRS, Chiba-shi, Japan M. Kase, S. Kubono RIKEN Nishina Center, Wako, Japan K. Kobayashi, M. Nishimura SHI Accelerator Service Ltd., Tokyo, Japan M. Oyaizu KEK, Ibaraki, Japan
	Light intensities of a grating monochromator during plasma chamber baking and 24Mg⁸⁺ and 48Ti¹³⁺ beam operation were observed at the Hyper-Electron Cyclotron Resonance ion source. During chamber baking almost all light intensities were Fe I and Fe II. However, when MgO or TiO2 rod was inserted into the plasma and the beam operation was started the light intensity spectrum was drastically changed and most of the Fe I and Fe II lights were disappeared and Mg or Ti light intensities were coming out. In this paper we describe vacuum conditions of ECR ion source during chamber baking and beam tuning.
	Poster WEPB29 [3.227 MB]